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US5113273A Expired / Lapsed US ⏱️ 0.0 years remaining

Liquid crystal display device

Assignee: Fujitsu Ltd
•
Filing: 1990-03-20
•
Granted: 1992-05-12
•
Expires: 2010-03-20
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Abstract

Abstract A liquid crystal display device comprising a layer of a ferroelectric liquid crystal material sandwiched between opposed first and second electrodes. The display device further comprises a dielectric layer as a capacitative element which is electrically connected through an electrically conductive connecting means to the first electrode so that the dielectric layer and the liquid crystal material are connected in parallel with regard to an external electric source. The display device provides a large area and high information content display, high contrast ratio display, and high gradation display, together with a stabilized memory effect.

Inventors

  • 👤 Akihiro Mochizuki
  • 👤 Hideo Hama
  • 👤 Mitsuaki Hirose

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 19:08
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/133345; G02F1/137; G02F1/139; G02F1/141

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 132 words
A liquid crystal display device which comprises a ferroelectric liquid crystal material sandwiched between a first electrode formed on a first substrate and an opposed second electrode formed through a dielectric layer on a second substrate, the dielectric layer being electrically connected through an electrically conductive connecting means with the first electrode so that the dielectric layer and the liquid crystal material are connected in parallel with regard to an external electric source for applying a pulsed voltage to the display device, and so that the dielectric layer is able to act as a capacitative element for extending a relaxation time of the spontaneous polarization of the liquid crystal material, the capacitative element having a capacitance which is one ofsubstantailly equivalent to and slightly higher than that of the liquid crystal material.
Claim 2
Dependent Claim 132 words
A liquid crystal display device which comprises a ferroelectric liquid crystal material sandwiched between a first electrode formed on a first substrate and an opposed second electrode formed through a dielectric layer on a second substrate, the dielectric layer being electrically connected through an electrically conductive connecting means with the first electrode so that the dielectric layer and the liquid crystal material are connected in parallel with regard to an external electric source for applying a pulsed voltage to the display device, and so that the dielectric layer is able to act as a capacitative element for extending a relaxation time of the spontaneous polarization of the liquid crystal material, the capacitative element having a capacitance which is one ofsubstantailly equivalent to and slightly higher than that of the liquid crystal material.
Claim 3
Dependent Claim 35 words
A liquid crystal display device according to claim 1, in which the first and second electrodes are a set of crossed transparent stripe electrodes and the device is driven as a simple matrix address system.
Claim 4
Dependent Claim 23 words
A liquid crystal display device according to claim 1, in which the capacitative element is a flat overcoat layer having a uniform thickness.
Claim 5
Dependent Claim 21 words
A liquid crystal display device according to claim 1, in which the capacitative element is a capacitor having a low polarity.
Claim 6
Dependent Claim 22 words
A liquid crystal display device according to claim 1, in which the capacitative element is a capacitor having polarity or reversed polarity.
Claim 7
Dependent Claim 17 words
A liquid crystal display device according to claim 5, in which the capacitor is an electrolytic capacitor.
Claim 8
Dependent Claim 21 words
A liquid crystal display device according to claim 1, in which the electrically conductive connecting means is an electrically conductive paste.
Claim 9
Dependent Claim 28 words
A liquid crystal display device according to claim 1, in which the liquid crystal material has composition as follows: ##STR22## in which C* denotes a chiral carbon atom.
Claim 10
Dependent Claim 19 words
A liquid crystal display device according to claim 1, which has an information content of 640×400 dots or more.
Claim 11
Dependent Claim 95 words
A liquid crystal display device according to claim 1, which comprises a glass substrate as the first substrate having applied thereon, in sequence, a stripe indium-tin oxide coating as the first electrode, layer of the ferroelectric liquid crystal material, a stripe indium-tin oxide coating as the second electrode perpendicular to the first electrode, the dielectric layer supporting the second electrode, a glass substrate as the second substrate, and a silver paste as the connecting means sandwiched between the first electrode and the dielectric layer as well as the external electric source connected with the device.
Claim 12
Dependent Claim 23 words
A liquid crystal display device according to claim 2, in which the capacitative element is a flat overcoat layer having a uniform thickness.
Claim 13
Dependent Claim 21 words
A liquid crystal display device according to claim 2, in which the capacitative element is a capacitor having a low polarity.
Claim 14
Dependent Claim 23 words
A liquid crystal display device according to claim 2, in which the capacitative element is a capacitor having a polarity or reversed polarity.
Claim 15
Dependent Claim 17 words
A liquid crystal display device according to claim 13, in which the capacitor is an electrolytic capacitor.
Claim 16
Dependent Claim 21 words
A liquid crystal display device according to claim 2, in which the electrically conductive connecting means is an electrically conductive paste.
Claim 17
Dependent Claim 29 words
A liquid crystal display device according to claim 2, in which the liquid crystal material has a composition as follows: ##STR23## in which C* denotes a chiral carbon atom.
Claim 18
Dependent Claim 19 words
A liquid crystal display device according to claim 2, which has an information content of 640×400 dots or more.
Claim 19
Dependent Claim 95 words
A liquid crystal display device according to claim 2, which comprises a glass substrate as the first substrate having applied thereon, in sequence, a stripe indium-tin oxide coating as the first electrode, layer of the ferroelectric liquid crystal material, a stripe indium-tin oxide coating as the second electrode perpendicular to the first electrode, the dielectric layer supporting the second electrode, a glass substrate as the second substrate, and a silver paste as the connecting means sandwiched between the first electrode and the dielectric layer as well as the external electric source connected with the device.

References Cited (Backward Citations)

US4040720A Cited
DE3208611A1 Cited
JPS58176623A Cited
US4681404A Cited
US4738515A Cited
US4978203A Cited
US4836655A Cited
EP0257638A2 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-05-12 1995-11-11 1996-05-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-05-12 1999-11-11 2000-05-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-05-12 2003-11-11 2004-05-12 $7700.00 Window Closed / Lapsed

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